Sorry Folks, I'm having a total mental block here. Seeing several references to "E-glass" rods and have little (any?) idea what they are/primarily used for.

Waaaaay back in the day (Lamiglas still does a few of these) "S-Glass" was the transitional material from 'fiber glass' to graphite. Dear God those were great rods; only man-made product that had the qualities (the good ones) of a cane rod in hand.

If anyone ever decides to bring out a line of rods made with "S Glass" I'm going to be into these 'big bucks.' They were that good.

Mojo is going to be more informative here than I am, but here's what I think I know.

S-glass is, generally, going to give you a faster blank than E-glass. I frequently fish one of the Diamondback Diamondglass 3 wts., that has a good "fast" action for a glass rod. It's made from S-glass. I also have a TL Johnson fiberglass rod (8'0" 4 wt.) that's an S-glass blank; reinforced in places with carbon fiber.

The best E-glass rod blanks and rods are probably going to come from Mike McaFarland.

Again, Mojo will fill in the blanks on this post and make any corrections that are needed.

Pocono's correct about the S-glass being faster.
E-glass is about 10 million modulus. That's about average for a bamboo fly rod from what I've been told.
S-glass is about 12 million modulus- faster than E-glass. (Orvis' Superfine series is about 40 million modulus)
E-glass builders are as mentioned, Mike McFarland
Lamiglas has been building the E-glass Honey colored fly rods and blanks for years now and I think it's sadly coming to an end.
There are a lot of new designers, builders today working with glass, whether or not it's E, S, or like Pocono mentioned TL Johnson's Synergy (which I absolutely love) and that's S-glass over a low modulus carbon fiber scrim . One of my favorite rods.
Fred Paddock -beautifully designed E-glass
Larry Kenney- (one of the original owners of Scott fly rods) is now designing and building glass rods- e-glass using resin impregnated prepreg.
Another name that's synonymous in the fishing world- Tom Morgan- again working and designing rods with E-glass and Kerry Burkheimer is rolling them.
Kubuto glass rods out of Japan- totally unbelievable. Google it up.
Scott has a glass rod out again this year- S-glass.
Steffan Brothers- some of the best S-glass rods out there. Plain looking but arse kicking.
Sweetgrass now is offering a Drukman designed glass rod- Sam I guess has said adios to Winston and is working for Sweetgrass now and word has it from another birdie that Kerry Burkheimer is also rolling the rods that Sam is designing
And like Poc said Diamondback's Diamondglass is S-glass. For some unknown reason they're no longer being made- and they were a popular rod. With all the fiberglass fly rod interest in the past few years, I can't understand the thinking behind Cortlands decision to drop the line, except it's a corporate bull sh_t call by a bean counter. They just should have tried to sell the brand.
Supposedly TFO had a glass rod in their lineup last year but I think they were just testing the waters. Haven't heard anything about it lately.
There's more builders and designers out there and a lot are in Japan.
So there's just a few choices you have. I have E-glass, S-glass and hybrids. I also have to say I love my graphites. From slow to fast. Just depends on the mood I'm in and the waters and style of fishing I'm doing.
Anyway, what was the question again?